1. Field of the Invention
In one aspect, this invention relates to brake rotors suitable for use in caliper disk brake assemblies. In a further aspect, this invention relates to coated aluminum articles.
2. Prior Art
It is known to coat metal substrates with hard wear resistant materials for use in machining or wear applications. A common coating material is the cemented carbide coating or laminate on the faces of cutting tools. Cutting tool carbides normally comprise a high percentage on the order of 90% or more hard metal carbide in a matrix of binder metallic material generally chosen from the class of iron, nickel, and/or cobalt alloys. The amount of metallic material in this type of carbide is deliberately minimized, since the metal matrix is used essentially to hold the carbide particles in place, and the metal is considerably weaker and less wear resistant material than the carbide.
In the effort to decrease the weight in passenger vehicles, replacing a cast iron brake rotor with a similar sized rotor formed from aluminum or other light weight metal would save considerable weight. However, light metal rotors by themselves do not have sufficient abrasion resistance to perform satisfactorily in friction applications thereby necessitating a wear resistant coating. A wear resistant coating would also promote brake pad-rotor friction couple compatability to provide improved brake life and stopping characteristics.